Oscillation-generating system



UNITED STATES PATENT 'OFFICIEL 'LEWIs n. CLEMENT, or NEWARK, .NEW JERSEY, .sssrenon To WESTERN ELEcTnIc COMPANY, INCORPORATED, 0F NEW YORK, N. Y., A CORPORATION 0F NEW YORK.

USCILLATION-GENERATING SYSTEM.

I Application led September To all whom it may corwem' Be it known that I, LEwIs vM. CLEMENT, a citizen of the United States, residing at Newark, in the. county of Essex, State of New Jersey, have invented-certain new and useful Improvements iny O'sclllatlon-Generating Systems, of which the following 1s a full, clear, concise, and exact descriptlon.

This invention relates to electrical oscillation generators and is adapted .for use 1n connection with signaling and other transmission systems wherein there is Yused an audion or equivalent electrical discharge device for tions.

An object of the invention 1s to provide means for varying the frequency of an oscillator and simultaneously to automatlcally provide the proper plate coupling and feed-back coupling for any partlcular frequency at which the oscillator 1s set to oscillate.

A `further object is to provide a means suitable for use in signaling and other transmission systems for quickly changing the wave length, preferably by a single adjustment by the operator, whereby greater secrecy can be securedand interference avoided. v

Heretofore, in using certain transmitting systems employing a high frequency generator of the audion type when it was desired to change the wave length on which the signal was being transmitted, it was necessary to perform several operations to adjust the wave length, the coupling of the plate circuit tothe oscillation circuit and the coupling of the grid or input circuit to the oscillation circuit, as changes of one of these usually affected the others and after each change of wavelength a series of adjustments would be necessary. before transmission couldrecommence.A This invention is intended to prevent this loss of timeand furthermore to simplify the necessary operations that much less skill is required on the part of operators than has heretofore been the case. f

The invention is shown in the accompanying drawings wherein Figure 1 'is a diagram of a system involving the invention,

generating high frequency oscilla- `Speciilcation ot Letters Patent.

Patented Nov. 1, 1921. 3o, 191s. serial No. 256,247.

Fig. 2 is a detail view of a .clip connector,

shunted across :the grid and filament connections. The tube 6 is preferably of the highly evacuated type, the operation of which does not depend upon gas ionization. A switch shaft 10 carries contact arms 11, 12, 13 and 14 which engage respectively series of contact elements 15, 16, 17 and 18.

Elements 15 and 16 are connected to various points in coil 2, as shown, while elements 17 are connected by leads 19 to coil 3 which may conveniently be a strip of metal wound in a spiral. 3 the leads 19 may be flexible and terminate in clips or equivalent devices 20 (Figs. 1 and 2). A much finer adjustment `can be ,secured in this manner than'xi's possible where the smallest variation corresponds to a whole turn of a coil. In one form the body 21 of device 2O consistsof insulating material and contains a spring contact member 22 which is' held by screw'23 and is adapted to clamp. upon member 3. Lead 19 is connected to screw 23.- Contact elements 18 are each connected to one of a set of capacities 4 which are'selectively in parallel with capacity 4. Capacities 4 and 4 'may each be made variable if desired. l In operation, a change of wave length will be accomplished by changing the switch 10l from one position to another. This causes a simultaneous change in the value of the inductances 2 and 3 connected in the circuit between the anode lead 7 land the cathode lead 9 to device 6 and likewise a change in the value of capacity connected between the grid lead 8 and cathode lead 9 of device 6. The apparatus is preferabl adjusted for maximum efliciency at eac wave length an which it is desired to trans- For fine adjustments on coill mit signals. The wave length will depend upon all the constants of the oscillatory antenna circuit; the plate coupling will be detel-mined by the nature and magnitude of the portion of the oscillatory circuit between leads 7 and 9; and the grid or input copling by thenature and magnitude of the elements of the oscillatory circuit which are between the leads 8 and 9. By plate coupling is understood the coupling between the cathode-anode or plate circuit of the tube and the antenna circuit. By means of the connectors 20 a. very exact adjustment for wave length may be made at any time. A number of different wave lengths will be available, five in the present instance, and the operator canl switch from one to the other instantly. No adjustment need be made other than a single movement of a single switch. Theadvantages of such an arrangement will be apparent to those skilled in the art.

In order tovillustrate a complete system the associated tube 24 with input circuit 25, which is coupled to microphone circuit 26, are shown. These parts together with choke coil 427, high frequency choke coil 28, and battery 29 coperate with the oscillator system and function to produce modulated signaling waves in the antenna, since the amplitude of the oscillations generated in the antenna circuit will vary in accordance with variations of impedance of tube 24 which in turn varies in yaccordance withl sound waves acting upon the microphone.

The particular means described herein are not essential to carrying out the invention as many modifications in arrangement and design will be apparent to those skilled in radio telephony. The generic and specific features of novelty of the invention are defined in the claims.

What is claimed is:

1. In combination, a circuit, a pair of circuits coupled thereto, means for transferring wave energy from one of said pair of circuits to said first-named circuit, means for transferring wave energy from said firstnamed circuit to the other of said pair of circuits, anda common means for changing the tuning of said first-named circuit and simultaneously changing the couplings of said pair of circuits to a dierent value than would'result from the change of tuning alone'.

2. In combination, a tuned circuit, a pair i of circuits coupled thereto, means for transferring wave energy from one of said pair of c1rcu1ts to said tuned clrcult, means for transferring wave energy from said tuned circuit to the other of said pair of circuits,

and simultaneouslychanging the couplings tube, an antenna circuit, input and output circuits for said tubeeach having a coupling to said antenna circit, distinct means for varying the period of said antenna circuit and each of said couplings, a common operating means for Said distinct means whereby each of said couplings and the period of said antenna circuit are adjustable to several values mutually adapted to `one another.

5. In combination, a vacuum tube, means including circuits associated with saidy tube whereby it functions as an oscillation generator, said circuits including a tuned circuit, an input circuit for saidtube coupled thereto, an output circuit for said tube coupled thereto, means operable to change the period of said tuned circuit, and means controlled by the operation of said first-named means, to a given position to establish each of said couplings at a value appropriate to said changed period.

6. In combination, an electric discharge device, said device including voutput electrodes and input elements, an oscillation circuit, a portion of said circuit being connected betweenl said output electrodes and another portion being connected between said input elements, and a common means for changing the period of said circuit and changing the impedances of said portions. to values corresponding to the changed period.

7. In combination, a vacuum tube, a tuned circuit, means including circuit connections connecting said tube and said circuit whereby'oscillations are generated in said circuit by said tube, said tube having a cathode, an anode and an impedance varying element, a portion of said circuit being connected serially between saidanode and cathode and a portion of said circuit being connected between said cathode and element, switching means `for changing the period of said circuit, and means under theA control of said switching means for automatically establishing the impedance of each of said ortions ati-a value appropriate to each position rel'specti'vely of said switching means.

8. An oscillator comprising a space dis- @barge device, a tuned circuit, an input cir- 

